Changeset 88f4d44f in rtems for bsps/i386/pc386

bsps/riscv/riscv: Fix fe310_uart_read

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This fixes the riscv fe310 console driver fe310_uart_read function. The function
reads the RX status/data register to check if data is available, but discards
the data and reads it a seconds time.
Also cleared the interrupt enable bit in the first_open function.

Close #4719